the tire light in my car

I was coming home from my mothers when I noticed the illuminated tire signal. It was where the odometer is and not underneath my radio. This is the first time that I have seen this light.

I bought my smart in Wisconsin and drove it from there to Tempe Arizona where I live now.

The weather these past few days gets to 114 or better and summer is just starting. I do not have a garage to put the car in. Does anyone know what this light means? Is it safe to drive my car? Any information would greatly be appreciated.

You want to use a digital tire gauge. The old style 'pencil'type with the scale that comes out the end are not too accurate. I went a couple of days messing with the light on my car before I figured out my gauge was way off. Usually once the pressure is correct, the light will go out. You may have to recalibrate it by using the button below the radio, check your manual for the proceedure or check out the video:

For every 10 degrees of air temp difference, there is approx 1PSI tire pressure difference.

So, if your tires are OK in 100+ degrees and the temp drops to 60 at night, that would be a 4PSI drop and the smart TPMS activates at about 10% loss of suggested tire pressure (around 3PSI drop)?

Get this question all the time here on the first overnight cold spell, owner comes out in the morning and has a TPMS warning and freaks?

Check your pressure with a quality guage and then after you start the smart push the TPMS reset button under the radio. The dash icon will blink a few times and then go out.

IF you are driving and the TPMS light comes on, push the reset. That will set the TPMS to what the pressure is RIGHT NOW. If it comes on again within a few minutes, you have a tire issue that needs to be addressed soon (or a faulty TPMS sensor)?